code: def test_module():
      return Scaler(
          input_key="x", output_key="scaled_x", mean=2.0, std=0.3
      )
  
file_path: popmon/tests/popmon/base/test_module.py
imports: import numpy
  import pytest
  from popmon.base import Module
label_desc: Use image node_id 1 for calling a global function with example usage: test_module() and returns: Scaler